Facia borders are commonly used between outer walls and roofs to provide a structural and architectural transition. Where a transition is between a soffit and the roof, an elongate strip or board is attached to the nailing plate on the outer wall and overlies the upper end thereof. A molding strip is oftentimes used to provide the final transition with the roof.
The installation using lumber is well established. The material is relatively rigid and presents few problems in alignment or fastening. The advent of light weight pre-finished materials, such as aluminum trim strips, however, present installation, quality control, and decorative problems. The trim strips are commonly roll-formed on site from coiled stock, cut to convenient extended lengths, and nailed at the upper ends to the underlying nailing plate. Because of the thin wall material commonly used, 20 gauge or less in thickness, the formed strips are prone to deflection and sagging during installation, presenting an undesirable waviness at the bottom detracting from appearance. Unless carefully handled, the strips may also kink or buckle, further complicating installation and appearance. Thus, unless painstakingly matched to reference markings requiring advanced carpentry skills, the finished border is irregular and decoratively compromised.
Further, the fastener installation tends to impart localized surface blemishes, in the form of dimples and waves, which are likewise unattractive. Moreover, the rigid attachment of the trim strip presents thermal expansion problems that can produce bowings and other thermally related distortions of the trim strip. Not entirely satisfactory attempts have been made to overcome the attachment difficulties using adhesives, however, durability and long-term adherence problems persist.
Facia systems have been proposed using custom components, in both aluminum and vinyl stock. For instance, U.S. Pat. No. 6,272,797 to Finger discloses a rake board installation wherein upper and lower J-channels capture inwardly projecting hooks at the top and bottom of a trim piece. A similar custom retention system is disclosed in U.S. Pat. No. 4,461,128 to Knoebl wherein upper and lower mounting channels capture the facia panel. Another mounting system is disclosed in U.S. Pat. No. 3,332,180 to Price wherein spaced mounting clips engage the lower flange of a trim member, with the upper end of the trim member nailed to the roof sheeting. While each of the foregoing eliminates some of the drawbacks of current facia installation, custom and accordingly expensive components are required.